The Grounding of an Ice Shelf in the Central Arctic Ocean: A Modeling Experiment
A numerical ice sheet model was used in a first test towards evaluating the hypothesis that, during a period of large-scale glaciation, an ice shelf emanating from the Barents/Kara Seas grounded across parts of the Lomonosov Ridge to a depth of around 1000 m below present sea level (Jakobsson, 1999;...
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ftuninhampshire:oai:scholars.unh.edu:ccom-1285 2023-05-15T14:53:01+02:00 The Grounding of an Ice Shelf in the Central Arctic Ocean: A Modeling Experiment Jakobsson, Martin Siegert, M Paton, Mark 2003-01-01T08:00:00Z application/pdf https://scholars.unh.edu/ccom/286 https://scholars.unh.edu/cgi/viewcontent.cgi?article=1285&context=ccom unknown University of New Hampshire Scholars' Repository https://scholars.unh.edu/ccom/286 https://scholars.unh.edu/cgi/viewcontent.cgi?article=1285&context=ccom Center for Coastal and Ocean Mapping Computer Sciences Oceanography and Atmospheric Sciences and Meteorology text 2003 ftuninhampshire 2023-01-30T21:32:25Z A numerical ice sheet model was used in a first test towards evaluating the hypothesis that, during a period of large-scale glaciation, an ice shelf emanating from the Barents/Kara Seas grounded across parts of the Lomonosov Ridge to a depth of around 1000 m below present sea level (Jakobsson, 1999; Polyak et al., 2001). Despite that we not include complex ice shelf physics or grounding line mechanics in our model and treat the process of marine melting in a simple manner, our experiments are the necessary first steps toward providing a comprehensive reconstruction of the former ice-sheet/ice-shelf system in the Arctic Ocean. A series of model runs was performed where ice shelf mass balance and ice shelf strain per unit time (strain rate) were adjusted. The mass balance and shelf ice strain rate are the key model parameters that govern the flux of ice into the Arctic Ocean. Grounding on the Lomonosov Ridge was not modeled when the ice shelf strain rate was 0.005 year-1 (i.e. a free flowing ice shelf). Even with low rates (<10 cm/year) of basal melting, the ice shelf thickness was always less than 100 m over the central part of the ridge. Our experiment suggests that grounding on the Lomonosov Ridge by a free-flowing ice shelf is not possible. When the strain rate in the shelf ice was reduced to zero, however, the shelf thickness increased substantially. Such conditions are likely only to have occurred during periods of large-scale glaciation if substantial stagnant and thickened sea ice was present in the ocean, buttressing the ice shelf flowing from the Barents Sea. A comprehensive study using a coupled icesheet/ shelf/sea-ice model would build on these preliminary results and have the potential to further constrain the history of circum-Arctic Ocean ice sheets. Text Arctic Arctic Ocean Barents Sea Ice Sheet Ice Shelf Lomonosov Ridge Sea ice University of New Hampshire: Scholars Repository Arctic Arctic Ocean Barents Sea |
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University of New Hampshire: Scholars Repository |
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Computer Sciences Oceanography and Atmospheric Sciences and Meteorology |
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Computer Sciences Oceanography and Atmospheric Sciences and Meteorology Jakobsson, Martin Siegert, M Paton, Mark The Grounding of an Ice Shelf in the Central Arctic Ocean: A Modeling Experiment |
topic_facet |
Computer Sciences Oceanography and Atmospheric Sciences and Meteorology |
description |
A numerical ice sheet model was used in a first test towards evaluating the hypothesis that, during a period of large-scale glaciation, an ice shelf emanating from the Barents/Kara Seas grounded across parts of the Lomonosov Ridge to a depth of around 1000 m below present sea level (Jakobsson, 1999; Polyak et al., 2001). Despite that we not include complex ice shelf physics or grounding line mechanics in our model and treat the process of marine melting in a simple manner, our experiments are the necessary first steps toward providing a comprehensive reconstruction of the former ice-sheet/ice-shelf system in the Arctic Ocean. A series of model runs was performed where ice shelf mass balance and ice shelf strain per unit time (strain rate) were adjusted. The mass balance and shelf ice strain rate are the key model parameters that govern the flux of ice into the Arctic Ocean. Grounding on the Lomonosov Ridge was not modeled when the ice shelf strain rate was 0.005 year-1 (i.e. a free flowing ice shelf). Even with low rates (<10 cm/year) of basal melting, the ice shelf thickness was always less than 100 m over the central part of the ridge. Our experiment suggests that grounding on the Lomonosov Ridge by a free-flowing ice shelf is not possible. When the strain rate in the shelf ice was reduced to zero, however, the shelf thickness increased substantially. Such conditions are likely only to have occurred during periods of large-scale glaciation if substantial stagnant and thickened sea ice was present in the ocean, buttressing the ice shelf flowing from the Barents Sea. A comprehensive study using a coupled icesheet/ shelf/sea-ice model would build on these preliminary results and have the potential to further constrain the history of circum-Arctic Ocean ice sheets. |
format |
Text |
author |
Jakobsson, Martin Siegert, M Paton, Mark |
author_facet |
Jakobsson, Martin Siegert, M Paton, Mark |
author_sort |
Jakobsson, Martin |
title |
The Grounding of an Ice Shelf in the Central Arctic Ocean: A Modeling Experiment |
title_short |
The Grounding of an Ice Shelf in the Central Arctic Ocean: A Modeling Experiment |
title_full |
The Grounding of an Ice Shelf in the Central Arctic Ocean: A Modeling Experiment |
title_fullStr |
The Grounding of an Ice Shelf in the Central Arctic Ocean: A Modeling Experiment |
title_full_unstemmed |
The Grounding of an Ice Shelf in the Central Arctic Ocean: A Modeling Experiment |
title_sort |
grounding of an ice shelf in the central arctic ocean: a modeling experiment |
publisher |
University of New Hampshire Scholars' Repository |
publishDate |
2003 |
url |
https://scholars.unh.edu/ccom/286 https://scholars.unh.edu/cgi/viewcontent.cgi?article=1285&context=ccom |
geographic |
Arctic Arctic Ocean Barents Sea |
geographic_facet |
Arctic Arctic Ocean Barents Sea |
genre |
Arctic Arctic Ocean Barents Sea Ice Sheet Ice Shelf Lomonosov Ridge Sea ice |
genre_facet |
Arctic Arctic Ocean Barents Sea Ice Sheet Ice Shelf Lomonosov Ridge Sea ice |
op_source |
Center for Coastal and Ocean Mapping |
op_relation |
https://scholars.unh.edu/ccom/286 https://scholars.unh.edu/cgi/viewcontent.cgi?article=1285&context=ccom |
_version_ |
1766324429057425408 |